Ajax or XMLhttpRequest using applications still have a long way to go. Gmail is more definitely the most advanced and best such app. Here’s some discussion on the subject:
- QuirksBlog: Ajax, promise or hype?
- About “Combining XMLHttpRequest and Rails to Produce More Efficient UIs”
- Applied Ajax
- Usable XMLHttpRequest in Practice
- AJAX and Accessibility
(Strange – several blogs listed and none have trackbacks that I can see!)